/*************************************************************************
	> File Name: test_sem.c
	> Author: Thinking
	> Mail: program_code@sohu.com 
	> Created Time: Sat Sep 18 16:48:41 2021
 ************************************************************************/

#include <stdio.h>

#include <nettls/ssl.h>
#include <nettls/bn_mul.h>

#if !defined(MBEDTLS_CONFIG_FILE)
#include <nettls/config.h>
#else
#include MBEDTLS_CONFIG_FILE
#endif

#if defined(MBEDTLS_PLATFORM_C) //delete platfrom.h
#include <nettls/platform.h>
#else
#include <stdio.h>
#include <stdlib.h>
#define mbedtls_time       time 
#define mbedtls_time_t     time_t
#define mbedtls_fprintf    fprintf
#define mbedtls_printf     printf
#endif

#if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_ENTROPY_C) ||  \
    !defined(MBEDTLS_SSL_TLS_C) || !defined(MBEDTLS_SSL_CLI_C) || \
    !defined(MBEDTLS_NET_C) || !defined(MBEDTLS_RSA_C) ||         \
    !defined(MBEDTLS_CERTS_C) || !defined(MBEDTLS_PEM_PARSE_C) || \
    !defined(MBEDTLS_CTR_DRBG_C) || !defined(MBEDTLS_X509_CRT_PARSE_C)

#else

#include <nettls/net_sockets.h>
#include <nettls/debug.h>
#include <nettls/ssl.h>
#include <nettls/entropy.h>
#include <nettls/ctr_drbg.h>
#include <nettls/error.h>
#include <nettls/certs.h>

#include <string.h>

#define SERVER_PORT "443"
#define SERVER_NAME "110.242.68.4"
#define GET_REQUEST "GET / HTTP/1.0\r\n\r\n"

#define DEBUG_LEVEL 1

#endif


static void my_debug(void *ctx, int level,
	const char *file, int line,
	const char *str)
{
	((void)level);

	mbedtls_fprintf((FILE *)ctx, "%s:%04d: %s", file, line, str);
	fflush((FILE *)ctx);
}

int ssl() 
{
	int ret, len;
	mbedtls_net_context server_fd;
	uint32_t flags;
	unsigned char buf[1024];
	const char *pers = "ssl_client1";

	mbedtls_entropy_context entropy;
	mbedtls_ctr_drbg_context ctr_drbg;
	mbedtls_ssl_context ssl;
	mbedtls_ssl_config conf;
	mbedtls_x509_crt cacert;

#if defined(MBEDTLS_DEBUG_C)
	mbedtls_debug_set_threshold(DEBUG_LEVEL);
#endif

	/*
	* 0. Initialize the RNG and the session data
	*/
	mbedtls_net_init(&server_fd);
	mbedtls_ssl_init(&ssl);
	mbedtls_ssl_config_init(&conf);
	mbedtls_x509_crt_init(&cacert);
	mbedtls_ctr_drbg_init(&ctr_drbg);

	mbedtls_printf("\n  . Seeding the random number generator...");
	fflush(stdout);

	mbedtls_entropy_init(&entropy);
	if ((ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy,
		(const unsigned char *)pers,
		strlen(pers))) != 0)
	{
		mbedtls_printf(" failed\n  ! mbedtls_ctr_drbg_seed returned %d\n", ret);
		goto exit;
	}

	mbedtls_printf(" ok\n");

	/*
	* 0. Initialize certificates
	*/
	mbedtls_printf("  . Loading the CA root certificate ...");
	fflush(stdout);

	ret = mbedtls_x509_crt_parse(&cacert, (const unsigned char *)mbedtls_test_cas_pem,
		mbedtls_test_cas_pem_len);
	if (ret < 0)
	{
		mbedtls_printf(" failed\n  !  mbedtls_x509_crt_parse returned -0x%x\n\n", -ret);
		goto exit;
	}

	mbedtls_printf(" ok (%d skipped)\n", ret);

	/*
	* 1. Start the connection
	*/
	mbedtls_printf("  . Connecting to tcp/%s/%s...", SERVER_NAME, SERVER_PORT);
	fflush(stdout);

	if ((ret = mbedtls_net_connect(&server_fd, SERVER_NAME,
		SERVER_PORT, MBEDTLS_NET_PROTO_TCP)) != 0)
	{
		mbedtls_printf(" failed\n  ! mbedtls_net_connect returned %d\n\n", ret);
		goto exit;
	}

	mbedtls_printf(" ok\n");

	/*
	* 2. Setup stuff
	*/
	mbedtls_printf("  . Setting up the SSL/TLS structure...");
	fflush(stdout);

	if ((ret = mbedtls_ssl_config_defaults(&conf,
		MBEDTLS_SSL_IS_CLIENT,
		MBEDTLS_SSL_TRANSPORT_STREAM,
		MBEDTLS_SSL_PRESET_DEFAULT)) != 0)
	{
		mbedtls_printf(" failed\n  ! mbedtls_ssl_config_defaults returned %d\n\n", ret);
		goto exit;
	}

	mbedtls_printf(" ok\n");

	/* OPTIONAL is not optimal for security,
	* but makes interop easier in this simplified example */
	mbedtls_ssl_conf_authmode(&conf, MBEDTLS_SSL_VERIFY_OPTIONAL);
	mbedtls_ssl_conf_ca_chain(&conf, &cacert, NULL);
	mbedtls_ssl_conf_rng(&conf, mbedtls_ctr_drbg_random, &ctr_drbg);
	mbedtls_ssl_conf_dbg(&conf, my_debug, stdout);

	if ((ret = mbedtls_ssl_setup(&ssl, &conf)) != 0)
	{
		mbedtls_printf(" failed\n  ! mbedtls_ssl_setup returned %d\n\n", ret);
		goto exit;
	}

	if ((ret = mbedtls_ssl_set_hostname(&ssl, SERVER_NAME)) != 0)
	{
		mbedtls_printf(" failed\n  ! mbedtls_ssl_set_hostname returned %d\n\n", ret);
		goto exit;
	}

	mbedtls_ssl_set_bio(&ssl, &server_fd, mbedtls_net_send, mbedtls_net_recv, NULL);

	/*
	* 4. Handshake
	*/
	mbedtls_printf("  . Performing the SSL/TLS handshake...");
	fflush(stdout);

	while ((ret = mbedtls_ssl_handshake(&ssl)) != 0)
	{
		if (ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE)
		{
			mbedtls_printf(" failed\n  ! mbedtls_ssl_handshake returned -0x%x\n\n", -ret);
			goto exit;
		}
	}

	mbedtls_printf(" ok\n");

	/*
	* 5. Verify the server certificate
	*/
	mbedtls_printf("  . Verifying peer X.509 certificate...");

	/* In real life, we probably want to bail out when ret != 0 */
	if ((flags = mbedtls_ssl_get_verify_result(&ssl)) != 0)
	{
		char vrfy_buf[512];

		mbedtls_printf(" failed\n");

		mbedtls_x509_crt_verify_info(vrfy_buf, sizeof(vrfy_buf), "  ! ", flags);

		mbedtls_printf("%s\n", vrfy_buf);
	}
	else
		mbedtls_printf(" ok\n");

	/*
	* 3. Write the GET request
	*/
	mbedtls_printf("  > Write to server:");
	fflush(stdout);

	len = sprintf((char *)buf, GET_REQUEST);

	while ((ret = mbedtls_ssl_write(&ssl, buf, len)) <= 0)
	{
		if (ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE)
		{
			mbedtls_printf(" failed\n  ! mbedtls_ssl_write returned %d\n\n", ret);
			goto exit;
		}
	}

	len = ret;
	mbedtls_printf(" %d bytes written\n\n%s", len, (char *)buf);

	/*
	* 7. Read the HTTP response
	*/
	mbedtls_printf("  < Read from server:");
	fflush(stdout);

	do
	{
		len = sizeof(buf) - 1;
		memset(buf, 0, sizeof(buf));
		ret = mbedtls_ssl_read(&ssl, buf, len);

		if (ret == MBEDTLS_ERR_SSL_WANT_READ || ret == MBEDTLS_ERR_SSL_WANT_WRITE)
			continue;

		if (ret == MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY)
			break;

		if (ret < 0)
		{
			mbedtls_printf("failed\n  ! mbedtls_ssl_read returned %d\n\n", ret);
			break;
		}

		if (ret == 0)
		{
			mbedtls_printf("\n\nEOF\n\n");
			break;
		}

		len = ret;
		mbedtls_printf(" %d bytes read\n\n%s", len, (char *)buf);
	} while (1);

	mbedtls_ssl_close_notify(&ssl);

exit:

#ifdef MBEDTLS_ERROR_C
	if (ret != 0)
	{
		char error_buf[100];
		mbedtls_strerror(ret, error_buf, 100);
		mbedtls_printf("Last error was: %d - %s\n\n", ret, error_buf);
	}
#endif

	mbedtls_net_free(&server_fd);

	mbedtls_x509_crt_free(&cacert);
	mbedtls_ssl_free(&ssl);
	mbedtls_ssl_config_free(&conf);
	mbedtls_ctr_drbg_free(&ctr_drbg);
	mbedtls_entropy_free(&entropy);

#if defined(_WIN32)
	mbedtls_printf("  + Press Enter to exit this program.\n");
	fflush(stdout); getchar();
#endif

	return(ret);
}

